Known in the art are fuel supply systems in which the induction tube contains a standard air throttle and also an air flow metering flap or mechanism. The air flow meter is coupled to a suitable shaft encoder which generates a signal that is used in the subsequent preparation of a fuel injection control pulse. It is a distinct disadvantage of the known system that it requires two independent and separately movable control elements within the induction tube, i.e., the flap or valve and the metering flap of the air flow rate meter, thereby engendering substantial additional costs and complications.